Weather data are used by numerous entities such as government agencies and a variety of industries for analysis and informational purposes. For example, some industries that typically require accurate weather data include power traders, utility companies, insurance agencies, agriculture, and research institutions. Moreover, accurate data are critical for weather forecasting and meteorology, as well as for alternative energy planning and/or monitoring.
Atmospheric data is extracted from a variety of sources, including ground observations, satellites, upper atmospheric soundings, and surface-based radar. In most instances, the most valuable data for the entities that depend on accurate weather data are obtained from ground-based observation of a set of constantly measured atmospheric parameters such as temperature, pressure, humidity, hydrometeor data, wind, dewpoint, solar intensity, pollutants, and severe weather phenomena.
Often, a device called a weather station measures these atmospheric parameters. These devices are often transported to a location and operate unattended. Accordingly, it is desirable for the weather sensors used in a weather station to be compact, reliable, and accurate without intervention by the user.
For example, a conventional technology for detecting hydrometeors is described in U.S. Pat. No. 7,286,935. This precipitation detector comprises a detector attached beneath a rigid surface. The impact of hydrometeors on the surface causes the detector to output electrical signals associated with the impacts. In other conventional technologies, wind measurements are performed by devices such as a wind vane or a cup anemometer. Each of these devices, by their nature, requires moving parts. These moving parts are susceptible to several modes of failure. For example, dirt and ice may cause these conventional devices to seize and stop functioning. Over a long period of use, the moving parts of conventional devices are also susceptible to mechanical failure.
In addition, conventional technologies such as a cup anemometer or an impeller-based wind measurement unit have an intrinsic latent response to changing wind conditions and thus produce time-lagging data. In particular, the rotational inertia of the wind-flow collector prohibits sudden accelerations and decelerations that occur during sharp wind transients.
While some conventional solutions relate to anemometers with zero moving parts, these technologies also have drawbacks. For example, sonic anemometers require precise signal conditioning and are consequently often expensive. In addition, hot wire anemometers are liable to accumulate particulates that adversely affect the long term calibration of wind values.
Accordingly, it was realized that there was a need for a compact, inexpensive, anemometer that has no rotational moving parts.